Your brain has worked hard in 2018, so as the year draws to a close, take a moment to appreciate not only your marvelous network of brain cells, but those found in other species, too. Below is a list of where to find some of the year’s most stunning neuroscience images that reveal the hidden world of neurons in brilliant and breathtaking detail.

The Tetbow

In order to understand how the brain works, neuroscientists need to take a close look at how neuron networks are wired together. However this isn’t easy, after all just one cubic millimeter in the brain’s cerebral cortex contains around 50,000 neurons each making 6,000 connections with other neurons (give or take a few). Tracing a single network through this incredibly complex web is painstaking work. So, in recent years, researchers developed the Brainbow, a technique that allows individual neurons to be labelled with different fluorescent colors. Unfortunately, it still took months to trace the path of a single neuron across the mouse brain. To address this, in 2018 Takeshi Imai and his colleagues at Kyushu University, Kyoto University and the RIKEN Center for Developmental Biology in Japan took it to the next level. They developed the Tetbow, a method that produces extremely vivid colors enabling scientists to trace neuronal wiring across the whole mouse brain within a matter of days. Also, it’s really pretty.

Here we can see paths of neurons (colored threads) that reach to the region involved in memory and learning.

Z. Zheng et al./Cell 2018

The fruit fly brain contains around 100,000 neurons. In 2018 Davi Brock and his colleagues at the Howard Hughes Medical Institute created the world's first highly detailed map of the fly brain using a dataset of roughly 21 million images. In what has been called a 'tour de force' of technical accomplishment, the new map provides enough detail for scientists to now trace the connections between all the neurons in the fruit fly brain.

Many more images to explore...

For more glimpses into the beauty of neuroscience, don't forget the2018 Nikon Small World in Motion contest. First prize went to Elizabeth Haynes and Jiaye “Henry” He of the University of Wisconsin-Madison for their mesmerizing time-lapse video of a zebrafish embryo growing its sensory nervous system over the course of 16 hours. Using a technique called Light Sheet Fluorescence Microscopy, they visualized the developing embryo in 3D at 10x magnification. The result is as thought-provoking as it is beautiful.